He's Mine Now
by one-blue-eye
Summary: John stumbles out of bed and walks into another staring contest between Sherlock and his brother, Mycroft Holmes. It's the first time he's seen Mycroft since 'that night'.
1. Chapter 1

**Words**: Work In Progress  
**Categories**: M/M, Threesome - M/M/M  
**Fandom**: BBC Sherlock (TV)  
**Relationships**: Sherlock Holmes/John Watson, Developing Mycroft Holmes/John Watson, Developing Mycroft Holmes/John Watson/Sherlock Holmes

**Tags**: Jealous Sherlock, Morning After, Angst with a Happy Ending, John Watson is Holmes-sexual, Slow Burn, Mycroft is Naughty, Slash, Awkwardness, Flirting, Polyamory Negotiations, Sexual Content, Sexual Tension, Shameless Smut, Falling In Love, Voyeurism, Porn With Plot (or at the very least links to the other version)

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**HE MADE IT DOWN** to nearly the bottom rung before realizing they had company. He groaned softly and squeezed his eyes shut before murmuring a quiet, "_Mycroft,_" in greeting. It was both obvious and unsurprising that his presence was noted long before he'd noted theirs. Both eyes were already on him before he'd uttered a word.

He'd crawled out of bed only moments before, probably slammed the bathroom door behind him quite loudly before groaning into a long satisfying piss, which they'd probably noted as well. Privacy's a rare thing in 221B Baker Street, especially in the presence of both Holmes.

John met Sherlock's eyes and in return received a raised brow and an infinitesimal smile, which was not unusual as a form of greeting. Sherlock routinely managed to convey a great deal with a simple look and today was no exception. However, their lingering gaze was interrupted by Mycroft's delayed reply. He inclined his head solemnly and said, "_J-o-h-n_," in that silken-extended-meaning-laden way that he has. An unexpected tingling heat ran up John's spine, causing his eyes to nearly flutter shut and yet another inward groan.

He grimaced and managed a quiet, sarcastic, "Right. Great," each punctuated with a sharp final letter and slight shake of his head. He gripped the banister tightly before pushing off the last step.

Sherlock narrowed his pale eyes suspiciously and looked more closely between his brother and his best friend. He frowned at what he saw there. "John?" he prompted, causing John to stop midstride. He saw tension around John's eyes, deep creases across his forehead, a telltale stiffness in his shoulders and an unmistakably clenched left fist. The unfamiliar pang that spiked in his gut affirmed the mounting suspicion that he'd just missed something of import as it passed between them. "John? What's... great?" he asked again.

John released a sharp exhale through his nose and looked to the heavens, perhaps seeking some moral support before he said, "Oh, you know. Good thing it's not awkward or anything." He shook his head and slunk out of the room with impressive speed.

Sherlock shifted in his chair, making ready to follow John into the kitchen, with every intention of demanding an answer that made more sense but Mycroft held up a hand to stay him.

**"WAIT," HE SAID**, his voice barely above a whisper, drawing Sherlock's attention immediately.

Sherlock pinned him with a stare and demanded, "Explain!" He may have spoken at the same volume but his tone was far more urgent.

Mycroft took a few seconds to center his thoughts. Then he began, "Well, we did have sex the last time we saw each other." He paused just long enough for his words to sink in. He saw Sherlock flinch, reacting to an invisible pain. Then he continued. "He's probably feeling quite uncomfortable."

Initially, Sherlock reacted with denial, as he usually does. "No, he's not!" However, within, his Moderator reacted violently to the obvious falsehood. The mental prickling gave rise to the uncontrollable gnashing of teeth. Sherlock could lie to others, that was perfectly acceptable, but he'd long since trained his mind to refute such mendacities when directed at himself. He was forced to look away as Mycroft watched his internal struggle knowingly. With a firm grip on his back teeth he asked, "_Why_ is he?" He took a soothing breath and then added, "Why would that matter? He's having sex with me now—_not you_." To anyone else, his words would have sounded menacing but Mycroft, as always, was nonplussed.

"Yes. I understand that Sherlock, but most people form attachments when they have sex. These attachments tend to linger." Mycroft explained, not unkindly. He kept his voice soft and steady, hopefully providing a calming anchor for Sherlock's obvious and rising agitation.

Sherlock looked at him with wide eyes, as an array of implications flashed painfully before his mind's eye. His head swung towards the kitchen where John sat with his back to the two of them—ostensibly drinking his tea. Then he turned to Mycroft, his eyes drilling into his. "Have _you_?" he asked quietly.

Mycroft sighed, contemplated the merits of lying and then thought better of it. "Yes," he admitted quietly, "but it doesn't change anything."

Sherlock's eyes darkened and narrowed. Then his gaze was drawn inexorably towards the kitchen, where they settled on John's back. Within, the Judge chimed in, adding unhelpfully, _this is all your fault_.

Mycroft watched as his little brother bit his lip. He witnessed a vivid flare of consternation and regret as it twisted and paled Sherlock's face. It was so unlike him, to show such blatant emotion, that Mycroft took a sharp inward breath.

Sherlock turned towards him, snapped "What?!" He frowned, pursed his lips in frustration. He had no idea what he should do. No matter how hard he tried, this was not his area.

Mycroft pressed his pity down deep, set a mask upon his face before he asked, "Will you permit me to speak to him privately for a moment?" After a brief silent pause, Sherlock nodded.

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I do hope you enjoy this story. So far, I've written about 9 chapters. I'll post a chapter a week until I'm caught up. I'll give you links to A03 for any chapters rated more than "M". Read on for heaps of sexual tension, a bit'o angst and a good deal of smut...

Cheers!

blue


	2. Chapter 2

**JOHN TOOK A** steadying breath, a sip and then another breath before he asked, "Could you do me a favour?"

Mycroft waited patiently for him to continue. He watched as John willed his breathing under control. He watched as his eyes flared wide and then narrowed, as the fine facial muscles twitched under his skin, as his too honest body betrayed him. Irritation, frustration and arousal skittered across his face—for Mycroft, it was undeniable evidence of a losing battle being fought within.

"Could you just speak plainly for once? I've been awake for less than a bloody hour. I don't have the energy to deal with one of our usual cryptic conversations."

"That is precisely the point, John,' Mycroft countered, sounding far too reasonable, "this is nothing like our usual conversations. This situation is most certainly unique."

John grimaced and inclined his head slightly. "Mmm. I guess you do have a point." He sighed.

"You want me to speak plainly, yes?" he asked and waited for John to nod. "Then I will." He took a deliberate breath. "Sherlock is concerned that you and I have developed feelings for one another. I believe he is worried that he will lose you to me."

His heart jerked in his chest, he swore it did. While he struggled with that unnerving sensation, his skin started cooking from the inside out. It was only a matter of time until he started shivering. It was shock, he realized, mild as it was. Ridiculous. And yet… not entirely surprising considering the company that he kept. Still, John prided himself on his ability to remain cool under fire and it was an uncomfortable blow to bear at such an ungodly hour. John covered his seething face with both hands before swearing under his breath, "Jesus, Mycroft."

"You asked me to—"

"Yes—Yes—I _know_," he cut him off, hands still covering his eyes. Palpable tension was strung between them, thick and raw. "Christ, Mycroft. I don't even know what to say to that…"

Mycroft nodded silently, then realized John's eyes were firmly closed so he added, "I understand, John." His voice was soft and sympathetic.

Mycroft waited for what seemed like an eternity, listening to John breathe until his palms slid down his face and he finally uncovered his eyes. "Do you?" He asked quietly, still looking at the table.

Mycroft remained silent and still, feeling a little trapped.

John reached down, not too very far from the surface, found the stillness that comes when danger is afoot and with unerring bravery lifted his head. When finally their eyes met, Mycroft was pleased to find a gentle smile and kindness on John's open, honest face.

He may have smiled back. He must have because John's face shifted, he began searching and his eyes took on a familiar intensity. He saw behind them a determined struggle to understand.

He wasn't usually on the receiving end of this particular gaze. It was unnerving, seeing John look at him with eyes usually reserved for Sherlock.

What John saw there, Mycroft couldn't say for certain but whatever it was must have given him away because John licked his lips nervously and then asked, his voice almost a whisper, "Have you?"

When Mycroft met his eyes, his face was blank, relaxed even. He only hesitated briefly before answering. Prevarication wasn't an option. Not today. "Yes… John. I. Have." His voice was almost preternaturally gentle. It made John's gut clench, among other things.

There was a quick intake of breath and then John asked, "What am I supposed to do with that?" He sounded agonized. "I don't have a switch. I'm not like you. Or him. I can't do that."

**MYCROFT PULLED OUT **the chair opposite John and sat down quietly, a slight frown on his face now, as he mulled over his thoughts. He was surprised by John's words. He probably shouldn't have been. It was, after all, the demeanour he steadfastly portrayed. For some reason though, it was important that John know him better so he said, "I'm not a machine, John. I do have feelings. I do feel. I just don't choose to most of the time."

John sighed and shook his head. "Sometimes, I envy you."

"Why is that?" Mycroft asked carefully.

"I'd like to be able to do that. Choose not to feel. I wish it were that simple."

Mycroft nodded in understanding. "Our situation is not simple, as I'm sure you know, John. Sherlock made a decision and now he regrets it. At the time, he believed it was the best course of action."

"Well, he's a complete idiot sometimes!" John said sharply.

Mycroft smirked and gave a tight nod. "Yes, he is."

John let his hands fall to his lap and then he leaned forward. When he spoke, it was just above a whisper and to an onlooker his body language would've suggested they were a pair of conspirators. "I knew at the time, you know? But I did it anyways. To teach him a lesson I think." He huffed, and then added, "Kind of backfired though, didn't it?" Shaking his head, he pursed his lips and chuckled darkly.

Mycroft tapped a fingernail against the table top, arched a brow and then agreed wryly, "Yes, a bit."


End file.
